Book of Medical Disorders in Pregnancy - Tintash

along with the augmentation in cardiac
output and uterine blood flow, makes it a
good selection for the treatment of
gestational Hypertension.
If the diastolic blood pressure exceeded
110 mm Hg, Hydralazine (Apresoline)
can be administered as follows. A test
dose of 5 mg is injected as a bolus
intravenously and the blood pressure
monitored every 5 minutes. If the
diastolic pressure is not lowered to about
100 mm Hg in 20 minutes, a 10 mg dose
is similarly administered, and its effects
are monitored. This dose can be repeated
until the diastolic blood pressure is
lowered to about 100 mm Hg.
Rauwolfia compounds (Reserpine) –
The rauwolfia compounds interfere with
chemical neurotransmission at the post
ganglionic adrenergic nerve endings and
results in decreased peripheral vascular
resistance. The peripheral effect is a
result of depletion of terminal post
ganglionic catecholamine stores and
reduced catecholamine uptake, leading
to maximum catecholamine depletion in
24 hours. A second, though less
effective, hypotensive mechanism may
be a direct action on the vasomotor
center of the brain, secondary to
depletion of CNS catecholamines.
Because of the slow restoration rate of
tissue catecholamines, the antihypertensive
effect of Reserpine may last
several days after the final dose.
Increased parasympathetic activity can
result in bradycardia, nasal congestion,
increased salivation, cramps and
diarrhea. Other maternal side effects are
depression, increased water and sodium
retention, sedation and decreased plasma
renin levels. The major fetal com-
58
plication is neonatal respiratory difficulty
secondary' to nasal conges tion.
Despite the side effects and the
anesthetic risks of catecholamine depletion,
Reserpine is a good alternative antihypertensive
agent for both long-term
and acute management of gestational
hypertension.
Propranolol (Inderal) - Inderal is a beta
adrenergic blocking agent which decreases
the force and frequency of
myocardial contractions. This results in
reduction in cardiac output and an initial
elevation in peripheral vascular resistance,
which decreases with continued
drug usage. Chronic adminis-tration of
propranolol can cause a reduction in
plasma renin, possibly due to its direct
effect upon the kidneys. The result of
treatment is a decrease in systolic and
diastolic pressure, without orthostatic
hypotension. Reported maternal side
effects have been nightmares and
drowsiness. Use of propranolol in asthmatic
patients my lead to aggravation of
bronchospasm.
Beta blockade and the lowering of
cardiac output, have no place in the
management of hypertension during pregnancy.
Eclampsia - This is defined as disease in
which fits occur with pre eclampsia.
Clinical features - In this condition both
clonic and tonic convulsions occur, there
is often severe hypertension present. The
condition may occur during antepartum,
intrapartum or postpartum period. Most
frequently the complication occurs in the
last trimester and near term. Almost all
cases of postpartum eclampsia occur
within 24 hours after delivery 24 hours
is the usual limit given though some